Typewriting machine



May 9, 1933.

W. A. DOBSON.

TYPEWRITING MACHINE Filed April 19, 1930 INVENTOR:

'B'Y ma Patented May 9, 1933 PATEN T OFFICE WILLIAM A. noIssoN, or BEIDGEPORT, CONNECTICUT, AssIGNoE To UNnEEWoon ELLIOTT FISHER COMPANY, or NEW YoEK, N. Y., A CORPORATION or DELAWARE TYPEWRITING IVIACHINE Application led April 19,

This invention relates to the platen-carriage and its line-spacing mechanism in portable typewriting machines of the-Underwood class.

The portable machine is required to be compact, light, simple, inexpensive and not apt to get out of order, and it is the aim of this invention to provide a line-spacing mechanism which shall meet all the exacting requirements for an Underwood portable machine.

A feature of the present invention is a.

providing a pocket or confined space in which are assembled aline-space pawl and line-space regulator. The pawl at its rear end ispivoted to a short arm of a bellcrank line-space lever, the latter being pivoted upon an arm which is bent outwardly from the top of said carriage end plate.

The line-space pawl includes a body-portion which lies along the inner face of the `Carriage end plate, and at its rear is bent f over to form an ear which is pivoted to the line-space lever. The pawl has at its front end another bent-over ear to form a tooth for driving engagement with the ratchet-wheel` on the platen. The Vpawl has also at its front end an upwardly-projecting Camshaped tooth, the purpose of which is to engage a Cam-block which is fixed to the under side of the inturned flange on the carriage end plate, and by such engagement to lock the platen against overthrow.

The line-space wheel may be brought very close to the platen-frame end,V making it lin-1 necessary to prolong the carriage beyond the requirement-s for a portable machine, while it is also rendered practicable to employ a 1930. Serial No.` 445,544.

vleft-hand vplaten-knob upon the projecting lplaten-axle, said knob being beneath thelinespace lever, and lower than the bent-out' arm'which carries the latter.

The short arm of the bell-crank lever ex-y tends to a point back of the line-space wheel,V

but does not interfere with the travel of thel`v work-sheet around the platen, nor. make it necessary to reduce the width of the worksheet.

The overthrow tooth of the pawland the cam-block are both directly under the inturned ange of the end plate, so that stiiiness is secured, and consequent accuracy and reliability of the overthrow-preventing func tion. f Y drawn down at they A hollow bearing is outer end of the arm, and through; this is threaded a shoulder-screw, to form a stable fulcrum for the line-space lever. The

threaded stem of the screw extends far below the arm, and a hollow jam-nut orpshell is threaded thereon, theY jam-nut being of large diameter and housing the drawndown bearing. The upperedge or face of the nut is` of great diameter, andbears up against the bores ofthe arm and binds the screw very effectively. The bent-over arm and the described parts form an inexpensive andsolid mounting for the lever.

A stiffening rib may be provided where the arm is bent out from the carriage end plate, thus permitting the use of relatively light metal without undue weakness of the plate and arm.

TheV pawl 1s normally out of mesh with the line-space ratchet-wheel and slides back- Y ward and forward upon a rest that is mounted at the forward end of the pawl.r The rest is compound and shiftable, having two portions, either of which may be swung into use by means of a handle that is secured to the rest-device or regulator, which is pivoted to the inner face of the carriage end plate. One rest supports the pawl at a higher position than the other, so that the pawl niayv engage the Vratchetrwheel at a point to rotate the platen for either one or two line-spaces before it isfarrested by its overthrow stop. VThe handle-portion of ToA inafter appear.

In the accompanying drawing, Y

Figure 1 is a cross-sectional view, looking toward the left side of an TUnderwood portable typewriter, broken away in part, and

having my'invention applied thereto.

29.' Figure 5 is a 'frontjview of the left end F igure2 is a perspective view of the structure shown in Figure 1.

Figure 3 is an operational view, showing the drive-pawl engaging a stop-plug and preventing overthrow of the ratchet-wheel in a-well known way.

Figure 4 is. afdetail View illustrating a preferred construction for mounting the line-space lever.

of the typewriter shown inx Figure 1 broken awa in part. This view illustrates a preferred mounting of the line-space lever and the compact mounting of the drive-pawl for the platen ratchet-wheel. p Y 'In anv Underwood portable typewriting machine a usual platen 10 is mounted on a shaft 11. A linger-wheel 12 for rotating the platen is usually mounted on the righthand end of the shaft 11, which is journaled in a sheet-metal right end plate (not shown) and a sheet-metal left end plate 14 of -a usual` platen-frame 15.'

-v-The end plate 14 is bent inwardly to form ."iange-portions 1G and 17, and outwardly to form an arm 18. pressed with an integral stiffening rib 20.

Y'A line-space lever 21 has a huh 23'for receiving a pivot-screw 24 threaded in a downwardly-extending V1looss 25 drawn in the Vend of arm 18. A lock 26 having a cup form for housing vthe boss 25 may secure screw 24. Y

The lever 21 has a forwardly-extending L- arm 27 and an inreaching arm 28. Upon the under side of the inner end of the latter is mounted an integral flange 30 disposed approximately in a horizontal plane below the arm 28 and transversely disposed to the -plane of aV body-member 31 of a ratchetwheel drive-pawl generally designated as 32. The'left face of the body-member 31 is disposed against 'the right face of the left end plate 14,"which thereby helps to guide the pawl '32 in a vertical working plane. A tooth may be bent at right angles to the Vbody-'member 3l for engaging with teeth 34 of a ratchet-wheel 35 on the platen-shaftat lthe left end of the platen. To help keep the body-member 31 in position 'against the end plate 14 a down-reaching pin 36 is'fastened in a stop-block 37 which is strongly fastened against the under side of the in- C: reaching flange 16.

To Avprevent sudden engagement of the The latter may beV `to prevent overthrow. f

The full angular movement of the arm 28 Ais suflicient to move the pawl rearward a distance to rotate the platen 10 through a Vdoulole line-space. To determine whether the usual throw of the line-space lever is to rotate the platen a single or a double linespace, the starting position of the tooth 33 'may be varied or regulated for engaging a `differently positioned tooth 34 ofthe ratchetwheel 35. To this end, the flange 30 (see Figure 3) has anaperture slightly larger than a shoulder-screwV 40 passed through it for fastening it to thearm 28, and the length of a shoulder-portion 41 ofthe screw 40 is greater than the thickness of the sheet-metal stock of the flange 30. Also instrumentalities are provided adjacent the forward end of the pawl 32, between the end plate 14 and the platen 10, for supporting the pawl in a starting position for single line-spacing or double line-spacing. Y Y

According to the present invention, these supporting instrumentalities include a sheetmetal pawl-regulator member generally designated as 42 pivoted on a shoulder-screwA 43, which is threaded in a tapped hole in the end plate 14. The pawl-regulator member 42 has a forwardly-extending arm 44 whose outer end 45 has a tubular form for convenience when being grasped by an operators fingers.

the end plate 14 and `is connected by an integral inreaching oifset 46 to an inner armportion 47, which is disposed against the inner face of the end plate 14. rlhe offset 48 passes inwardly through a curved slot 48 in the end plate.

The pawl-regulator member 42 further includes two radial'pawl-supporting arms 5()v and 51 of unequal lengths, the arm 51 being shorter than the other and in the rear thereof, and each arm is provided with an inreaching lug 52. y The pawl 32 may rest on the lug 52of the longer arm 50, as shown in Figure 1, andthe pawl-tooth 33 is positioned for engaging a tooth 34 of the ratchet-wheel' The outer tubular end 45 is` disposed adjacent theouter or left face ofv tioned a distance from the rearinost position of the pawl-tooth which corresponds to two line-spaces.

To hold either of arms 50 or 51 in effective position, a detent-member 55 of spring metal After the lever 21 has been operated andv the arm 28 swung to its rearmost position, as determined by engagement of the beveled end of the lug 38 with the beveled block 37, the arm 28 and pawl 32 will be returned to starting position by a return spring 63 which has one end fastened to a downwardly-extending pin 64 in the arm 28, and the other end to the pin 36. As illustrated in Figure 5, the pin 36 will be notched at 65, whereby the spring 63 fastened to the pin will not bind the pawl 32 sliding between the pin and the end plate member 14.

It will be seen at Figure 5 that the plat-en is lengthened out until the line-space wheel 35 is brought right up to the end 14 of the platen-frame, so that the flange at the top thereof practically overlies the line-space wheel 35. rlhis leaves a greatly contracted space between the line-space wheel and the platen-frame end 14, but the line-space train is packed. within this limited space by eliminating the bulky slide heretofore employed. The pawl is placed against the inner face of the platen-frame end 14, under the flange 16, and is confined by means of a pin 36 thrust down from the flange; the pawl working in the space between the pin and the flange, and being readily withdrawable or insertible into said space by passing it under said pin.

The pawl so placed is operable by means ot the line-space lever, an ear being bent inwardly from the pawl and pivoted'upon a shoulder-screw which passes up through the pawl-ear and into the arm 28 of the linespace lever. Said arm at its work end terminates within the platen-frame, and at its outer end is mounted upon a shoulder-screw, which is threaded into the supporting arm 18 that is bent outwardly from the top of the end of the platen-frame. This gives the pivot 40 of the arm sufficient swing in a substantially straight line, to operate the line-space pawl, and the latter is loosely mounted upon the screw 40, to permit its front end to vibrate over the teeth of the line-space wheel.

he platen-knob 12, which approximates the diameter of the platen 10, is disposed close to the outer side of the platen-frame end 14; and the forwardly-extendingarm of the line-space lever 21 is arched Vover the knob 12, to give ample room for the play of the fingers in manipulating said knob; both the supporting arm 18 and the bell-crank arm 28 being spaced substantially in rear of the platen-knob 12, to give ample finger clearance. i

In order to make it feasible to use a supporting arm 18 bent out from the platenframe end, the latter is stilened by the struck-up rib 20. The shoulder-screw. 41 is hreaded down through a long bearing provided by a rib 25 in the outer end of the arm, this rib being housed by the nut 26, which is in the form of a cup, enclosing said bearing 25. By reason of its great diameter, the nut harmonizes with the hub y23 and also secures av strong frictional purchase upon the under side of the arm 18.

One of the solutions of the problem of compactness resides in the improved construction of the line-space regulator, which is a plate placed beneath the line-space pawlA 32, and held against the inner face of the platen-frame end 14 by means of shoulderscrew 43, and having bent-out rests'for theI pawl, to vary its Vline-spacing effect. This regulator passes out through a slot in the platen-frame end, and is bent forwardlyto. form an operating handle 45; the screw 43 also securing a spring-.plate 55, which detams the line-space regulator at either positron. his regulator is compactly confined under the pawl and under theflange' 16 of the platen-frame end, and-.is simple, inexpensive and reliable. i l f Variations may be resorted to within the scope of the invention, and portions of the improvements may be used Without others. 1 Having thus described my invention, I claim:

1. In a portable typewriting machine, the combination with a platen, of a platen-frame having an end inthe form of a plate having an inward top flange juxtaposed to the platen, and a line-spacing train in the form oi" a bell-crank lever pivoted at its elbowv upon an arm bent outwardly from the `to-p of said end plate, appawl lying beneath said flange and flat against the inner face of said end plate and having an inwardly-directed" ear` bent therefrom and lheld `up against the inner end of said lever-arm by a universal" joint, and a guide for the pawl extending down from said flange; the lever with the attached pawl forming a unit detachable from and attachable to said end plate.

2. ln a portable typewriting machine, the

combination with a platen, of a platen-framehaving an end in the form of Va plate having an inward top flange juxtaposed to the platen, and a line-spacing train in the form of a bell-crank lever pivoted at its elbow upon `an arin bent outwardly from the to of said'end plate, a pawl lying beneath sait flange and flat against the inner face of said end plate and having an inwardly-directed ear :bent therefrom and held up against the inner end of said lever-arm by a universal joint, a guide for the pawl extending down from said flange; the lever with the attached pawl forming a unit detachable from and attachable to said end plate, a shoulderscrew whereon said leveris mounted, said screw threaded down through a boss drawn in said supporting arm, and a nut in the form of a cup threaded upon said screw and housing said boss.

'3. In a portable typewriting machine, the

combination with a platen, of a platen-frame having an end in the form of a plate having an inward top Yflange juxtaposed to the platen, and a line-Spacing train 1n the form Vof a bell-crank lever pivoted at its elbow upon an arm bent outwardly from the top of said end plate, a pawl lying beneath said flangeand flat against the inner face of said Y end plate and having an inwardly-directed ear bent therefrom and held up against the inner end of said lever-arm by a universal joint, anda guide for the pawl extending down from said flange; the 'lever with the attached pawl forming a unit detachable from and attachable to said end plate, the pawl-pivot moving in an approximately straight line tov an extent sufficient to linespace the platen, and the pawl being loosely mounted upon the pivotto permit it to vibrate over the teeth of the linespace wheel.V

4. In aportable typewriting machine, the combination with a platen, of a platen-frame having an end in the form of a plate having an inward top flange juxtaposed to the platen, and a line-spacing train in the form of a bell-crank lever pivoted at its elbow upon an arm bent outwardly from the topof' said end plate, a pawl lying beneathY said flange and flat against the inner face of 'said end plate and having an inwardly-y directed ear bent therefrom and held up against the inner end of said lever-arm by a universal joint, a guide forthe pawl extending down fromsaid flange; the lever with the attached pawl forming a unit detachable Jfrom andV attachable to said end plate, and a platen-knob of approximately the diameterof the platen and connected thereto and disposed close to the outer side of said plat# en-frame end, the forwardly-extending arm of' said line-space lever being arched Y over the platenknob, and said outwardly-bent arm of' the platen-frame being sufliciently in ear of said knob to afford linger-room there- 5. In a portabletypewriting machine, the

combination with a platen, of a platen-frame having an end in the form of a plateV having an inward top flangejuxtaposed to the platen, and a line-spacing train in the form of a bell-crank lever pivoted at its el. bow upon an arm bent outwardly from the top of said end plate, a pawl lying flat against the inner face of said end plate and having an inwardly-directed ear bent therefrom and held up against the inner end of said lever-arm bya pivot, a guide for the pawl extending down from said flange; the lever with the attached pawl forming a unit detachable from and attachable to said end plate, and a regulator in the form of a plate also lying against the inner face of said platen-f'rame end and beneath said pawl, a shoulder-screw holding said plate against the inner face of the platen-frame end, said regulator having bent-over rests for the pawl, to vary its line-spacing effect.

6. In a portable typewriting machine, the combination with a platen, of a platenframe having an end in the form of a plate having an inward top flange juxtaposedA to the platen, and a line-spacing train in the form of a bell-crank lever pivoted at its elbow upon an arm bent outwardly from the top of said end plate, a pawl lying fiat against the inner face of said end plate and having an inwardly-directed ear bent therefrom and held up against the inner end of said lever-arm by a pivot, a guide for the pawl extending down' from said flange; the lever with the attached pawl forming a unit detachable from and attachable to said end plate, a regulator in the form ef a plate also lying against the inner face of said platen-V frame end and beneath said pawl, a shoulder-screw holding said plate against the inner face of the platen-frame end, said regulater having bent-over rests for the pawl, to vary its line-spacing effect, said regulator having an operating arm passing out through a slot in the platen-frame end, and .bent for- WILLIAM A. Doesonf 

